Bed Sheets and Securing Straps for Same

ABSTRACT

The present invention relates generally to bedding, and more particularly to beddings that combines a fitted sheet and top sheet into a single unit and employs a set of straps to secure the same in place on a mattress in order to minimize sheet movement during sleep to maximize sleep comfort and ease the bed-making process.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit under 35 U.S.C. 119(e) of U.S. Provisional Application Ser. No. 61/668,120, filed Jul. 5, 2012.

FIELD OF THE INVENTION

The present invention relates generally to bedding, and more particularly to beddings that combines a fitted sheet and top sheet into a single unit and employs a set of straps to secure the same in place on a mattress in order to minimize sheet movement during sleep to maximize sleep comfort and ease the bed-making process.

BACKGROUND OF THE INVENTION

A known problem in the field of bedding is sheets being moved about, or even becoming completely separated from the bed, by body movement during sleep. Such movement can lead to sleep disruption or discomfort, for example by way of temperature issues caused by loss of coverage of the body by a displaced top sheet or by way of bunching up of a loosened bottom sheet under the body, and other problems, such as direct exposure of the mattress to sweat when a loose bottom sheet is dislodged from beneath a sleeper.

Prior solutions to such bedding displacement issues have been proposed, including use of straps to secure or tie-down the fitted bottom sheet to the mattress to better resist movement thereof, and combining of a top sheet and fitted bottom sheet into a single unit to reduce top sheet movement by anchoring of same to bottom sheet that is fitted onto the mattress.

Examples of strap arrangements for securing bedding in place include those disclosed in U.S. Pat. Nos. 4,891,856, 6,161,235, 3,092,848, 4,040,133, 6,233,764 and U.S. Patent Application Publications 2009/0172881, 2009/0241261 and 2012/0060285.

Examples of combined fitted and top sheets include those disclosed in U.S. Pat. Nos. 5,375,274, 5,729,847, 5,901,389, 6,725,477, 7,100,223, 7,231,679, 7,487,561, 7,290,301.

Other bedding related prior art includes U.S. Pat. Nos. 7,810,184, 2,326,399, 4,045,832, 5,263,212, and U.S. Patent Application Publication 2004/0060113.

There remains room for improvement however, and applicant has developed a new combination sheet and securing strap product present advantages over the prior art solutions.

SUMMARY OF THE INVENTION

According to a first aspect of the invention there is provided a bed sheet for a mattress having a top surface, a bottom surface, a pair of first and second longitudinal sides, opposing head and foot ends, and corners defined between the longitudinal sides and the head and foot ends, the bed sheet comprising:

a center fabric portion for overlying the top surface of the mattress;

a plurality of hanging portions including:

-   -   hanging head and foot portions for hanging over the head and         foot ends of the mattress from opposing ends of the center         fabric portion;     -   first and second hanging side portions for hanging over the         first and second longitudinal sides of the mattress from         opposite sides of the center fabric portion; and

sheet fastener elements disposed on multiple ones of said hanging portions; and

flaps disposed on the multiples ones of said hanging portions and each being movable between a fastener-concealment position lying over at least one of the sheet fastener elements and a fastener-access position withdrawn from over said at least one of the sheet fastener elements.

Preferably the bed sheet is provided in combination with securing straps having strap fastener elements thereon that are positioned adjacent ends of said securing straps and selectively engagable to the sheet fastener elements of the bed sheet, the securing straps being dimensioned to span under the bottom surface of the mattress and reach upward therefrom at some or all of the sides, ends and corners of the mattress for attachment of the strap fastener elements to the sheet fastener elements to secure the bed sheet in place on the mattress, wherein movement of the flaps between the fastener-access and fastener-concealment positions enables exposure of the sheet fastener elements for attachment of the strap fastener elements thereto and subsequent concealment of said attachment from sight.

Preferably each flap has a flap fastener element thereon at a position that faces the sheet fastener element when said flap is in the fastener-concealment position over said sheet fastener element.

Preferably the flap fastener element and the sheet fastener element are non-engagable with one another.

Preferably the flap fastener element and the sheet fastener element are of a same one of either hook material or loop material of a hook and loop fastener.

Preferably a one of the flaps that is movable into and out of the fastener-concealment position over said sheet fastener element has a flap fastener element on a side of the flap that faces the sheet fastener element when said flap is in the fastener-concealment position, and a one of the securing straps for connecting to said sheet fastener element has a second strap fastener element on a side of said strap opposite the strap fastener element, the flap fastener element and the second strap fastener element being selectively engagable with one another.

Preferably the sheet fastener elements and flap fastener elements are of a same first type of fastener element, and the strap fastener elements on both sides of each strap are of a second type of fastener element engagable with the first type of fastener element.

Preferably the sheet fastener element and the strap fastener element are opposing ones of hook material and loop material to cooperatively form a first hook and loop fastener, and the flap fastener element and second strap fastener element are also opposing ones of the hook material and loop material to cooperatively form a second hook and loop fastener.

Preferably the sheet fastener element and the flap fastener element are the same one of either hook material or loop material.

Preferably the sheet fastener element and the flap fastener element are both loop material.

Preferably the bed sheet is a combined top and bottom sheet in which the hanging foot portion is part of a top sheet of the combined top and bottom sheet and the hanging head and side portions are part of a bottom sheet of the combined top and bottom sheet, and the fastener elements include top sheet fastener elements on the top sheet and bottom sheet fastener elements on the bottom sheet.

According to a second aspect of the invention there are provided securing straps for securing a bed sheet to a mattress by spanning of the straps beneath the mattress for connection of ends of said straps to the sheet at sheet fastener elements thereon at spaced apart positions around the perimeter of the mattress, the bed sheet having flaps movable into and out of fastener concealing positions over the sheet fastener elements and having flap fastener elements located on sides of the flaps that face the sheet fastener elements when the flaps are in the fastener concealing positions, wherein the securing straps comprise first and second strap fastener elements on opposite sides of each strap at a locations adjacent the ends of said straps, the first strap fastener element and the second strap fastener element being releasably engagable to the sheet fastener element and the flap fastener element, respectively.

According to a third aspect of the invention there are provided combined top and bottom sheets for a mattress having a top surface, a bottom surface, a pair of first and second longitudinal sides, opposing head and foot ends, a top transverse edge defined between the top surface and the foot end, a bottom transverse edge defined between the bottom surface and the foot end, a top longitudinal edge defined between the top surface and each longitudinal side, a bottom longitudinal edge defined between the bottom surface and each longitudinal side, and upright corners defined between the foot end and the longitudinal sides, the combined top and bottom sheets comprising:

a bottom sheet having a center portion for overlying the top surface of the mattress, head and foot portions for hanging over the head and foot ends of the mattress from opposing ends of the center portion, and first and second side portions for hanging over the first and second longitudinal sides of the mattress from opposite sides of the center portion;

a top sheet comprising a main portion overlying the central portion of the bottom sheet, lateral portions overlying the side portions of the bottom sheet on opposite sides of the main portion of the top sheet, and an end portion overlying the foot portion of the bottom sheet at a respective end of the main portion of the top sheet, the end portion of the top sheet spanning beyond sides of the foot portion of the bottom sheet to also overlie an end of each side portion of the bottom sheet adjacent the foot portion thereof so that the end portion of the top sheet has wrapped ends that wrap around the corners of the mattress from the foot end of the mattress to the longitudinal sides thereof, and each lateral portion of the top sheet comprising a folded-under end that underlies a remainder of the lateral portion of the top sheet and that overlies and forms a folded connection with a respective one of the wrapped ends of the end portion of the top sheet;

transverse stitching attaching the end portion of the top sheet to the foot portion of the bottom sheet in a transverse direction at a distance from the center portion of the bottom sheet so as to place the transverse stitching along the bottom transverse edge of the mattress; and

upper longitudinal stitching attaching the top sheet to the bottom sheet in a longitudinal direction at the folded connection between the folded-under end of each lateral portion of the top sheet and the respective one of the wrapped ends of the end portion of the top sheet so as to place the upper longitudinal stitching along the top longitudinal edges of the mattress adjacent the foot end of the mattress, the remainder of each lateral portion of the top sheet being free of the longitudinal stitching so that only the folded-under end of said lateral portion is attached to the bottom sheet by said longitudinal stitching;

wherein the bottom sheet and the top sheet are unattached to one another where the bottom sheet transitions from the central portion of the bottom sheet to the foot portion thereof so as allow relative movement between the sheets at the top transverse edge of the mattress.

Preferably there is provided lower longitudinal stitching attaching the wrapped ends of the end portion of the top sheet to the side portions of bottom sheet in the longitudinal direction at a distance further from the center portion of the bottom sheet than the upper longitudinal stitching so as to place the lower longitudinal stitching along the bottom longitudinal edges of the mattress, the lower longitudinal stitching only partially spanning a length of the side portions of the bottom sheet in the longitudinal direction.

Preferably the distances' of the lower longitudinal stitching and the transverse stitching from the center portion of the bottom sheet are equal.

Preferably the lower longitudinal stitching at each side portion of the bottom sheet forms a continuous seam with the transverse stitching.

Preferably the transverse stitching fully spans the foot portion of the bottom sheet in the transverse direction.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings, which illustrate exemplary embodiments of the present invention:

FIG. 1 is an overhead plan view of a bedding harness of the present invention employing a number of straps that span out from between a mattress and box-spring to connect to a fitted bed sheet on the mattress at locations around the perimeter of the mattress to hold the fitted sheet in place.

FIG. 2 is an overhead perspective view of combined fitted and top sheets of the present invention, which include features for fastening to and concealing the straps of FIG. 1, and employs a unique configuration of folds and stitch lines to optimize the balance between available foot room and anchoring of the sheets in place, while also providing consistent, cleanly folded sheet corners at the foot of the bed.

FIG. 3 is a perspective view of the combined fitted and top sheets of FIG. 2 with a lateral side portion of the top sheet shown lifted to a generally horizontal position from its natural position hanging vertically at the side of the bed.

FIG. 4 is a perspective view of the combined fitted and top sheets of FIG. 3 with the lateral side portion of the top sheet lifted further to reveal normally concealed stitching that attaches the top sheet to the bottom sheet at a folded-under end of the lateral side portion.

DETAILED DESCRIPTION

FIG. 1 shows a bedding harness 10 of the present invention, which features a number of straps 12, 14, 16 crossing over one another and sewn or otherwise foxed together at their lengthwise centers. The drawing shows the perimeter of a mattress and box-spring combination in broken lines, thus outlining the head end 102, foot end 104, and two longitudinal sides 106, 108 of the mattress 100, each of which aligns with the corresponding perimeter side of the box-spring on which the mattress is positioned in a conventional manner. The harness 10 is placed atop the box spring 200 so as to reside beneath the underside of the mattress.

The length of each strap 12, 14, 16 is sufficient to span fully across the bottom surface of the mattress in a respective direction so that the ends of the strap extend a short distance outward from between the mattress and box-spring. The illustrated embodiment features three straps, particularly a shorter strap 12 spanning across the mattress in a transverse direction parallel to the ends of the mattress and perpendicular to the longitudinal sides thereof, and two longer straps 14, 16 of equal length that each lie in a diagonal direction relative to the generally rectangular shape of the mattress so as to reach from one corner of the mattress to an opposing corner thereof.

As opposed to a number of full-length straps interconnected at their centers and each continuously spanning fully across the mattress to reach outward therefrom at two opposing points around the mattress perimeter, the harness may alternatively employ twice the number of half-length straps that are all connected together at inner ends thereof under the mattress, and each reaching outward from under the mattress at only one point around the mattress perimeter. The number of points, and location of these points, at which the harness reaches out from under the mattress may be varied from those shown in the illustrated embodiment, where six strap ends reach out from the mattress at the four corners thereof and two intermediate locations along the mattress sides.

Adjacent each strap-end extending out from under the mattress, each strap features two pieces of hook material 18 sewn to the two opposing sides or faces of the strap, for example hook material from a Velcro™ brand hook and loop fastener.

FIGS. 2 and 3 show a combined top and bottom sheet 30 of the present invention. The bottom fitted sheet 32 features the same general shape as a conventional, commercially available fitted sheet, with a conventional fabric span that includes a generally rectangular center portion 34 for overlying and fully covering the top surface 110 of the mattress, and head end portion, foot end portion and two side portions that surround the center portion on respective sides thereof to hang downward over the head, foot and sides of the mattress when the fitted sheet is in place thereon.

In the drawings, only the center portion 34, foot end portion 36, and one side portion 38 of the bottom sheet are visible, but it will be appreciated that the head and foot end portion match, as do the two side portions. In a conventional manner, elastic material at the corners of the fitted sheet where the side portions join to the end portions, or elastic material running around the full perimeter of the fitted sheet, may be used to help secure the corners in place under the mattress when the free outer edges of the end and side portions of the fitted sheet are tucked under the mattress in the space between the mattress and box-spring.

One way in which the combined top and bottom sheets 30 differ from the prior art is in the configuration of the top sheet 50 and its attachment to the to the bottom sheet 32.

The top sheet 50 features a rectangular main portion 52 that overlies the center portion 34 of the bottom sheet 32, spanning the full transverse width of the bottom sheet's center portion 34 and spanning all, or at least a majority of the longitudinal length thereof. From the main portion 52 of the top sheet 50, two lateral portions hang down on opposite sides of the main portion 52 to overhang respective sides of the top of the mattress to lie over the side portions 38 of the bottom sheet. In the drawings, only one of the lateral portions 54 of the top sheet is visible, and is shown in a raised position lifted from its naturally hanging position depending down the side of the mattress. A single end portion 56 of the top sheet 50 hangs down from the end of the main portion 52 at the foot of the mattress to lie over the foot end portion of the bottom sheet 32. The top sheet is formed by folding of an originally rectangular sheet and sewing of the same to the bottom sheet in the manner described herein further below.

The end portion 56 of the top sheet 50 spans a width greater than that of the foot end of the mattress, and thus also greater than that of the foot end portion of the bottom sheet 30. As a result, the end portion 56 wraps around the two mattress corners at the foot end of the bed, reaching partially over the two sides of the mattress toward the head of the bed. Each wrapped end 56 a of the end portion 56 reaching a partial distance along the respective side of the mattress has its bottom edge sewn to the respective side portion 38 of the bottom sheet beneath it, as shown at 58. This stitching 58 thus runs along the horizontal bottom edge of the respective longitudinal side of the mattress over a partial length thereof from the foot end of the mattress.

With the illustrated top sheet formed from a continuous, unitary rectangular piece of fabric, the wrapped end 56 a of the end portion 56 of the top sheet 50 is integrally linked to the respective lateral portion 54 of the top sheet 50, and more particularly to a folded-under triangular end 54 a of the later portion 54. The folded under end 54 a of the lateral portion 54 is sewn to the bottom sheet 32 along the boundary between the bottom sheet's center portion 34 and respective side portion 38, as shown at 60. This stitching 60 spans along the fold at which the folded-under triangular end 54 a of the lateral portion 54 of the top sheet transition is folded to transition itself into the wrapped end 56 a of the top sheet's end portion 56. Accordingly, this stitching 60 runs along the horizontal top edge of the respective longitudinal side of the mattress over a partial length thereof from the foot end of the mattress.

As stitching 60 engages only through the triangular folded-under end 54 a of the lateral portion, and not through the remaining rectangular upper layer of the lateral portion 54 that lies over the folded-under end, the upper layer of the lateral portion is not directly attached to the bottom sheet, and the stitching 60 is not normally seen, hence being shown in broken lines in FIGS. 2 and 3. FIG. 4 shows the lateral portion of the top sheet fully lifted from over the side of the bed to reveal the diagonally folded-under triangular end 54 a of the lateral portion of the top sheet, its integral connection to the respective wrapped end 56 a of the end portion of the top sheet, and the stitching 60 attaching the folded-under and wrapped ends 54 a, 56 a of the lateral and end portions of the top sheet to the underlying bottom sheet.

The attachment of the top sheet 50 to the bottom sheet 32 is completed by sewing of the end portion 56 of the top sheet to the foot end portion 36 of the bottom sheet at the free edge of the top sheet's end portion 56 furthest from the top sheet's main portion, as shown at 62. This stitching 62 thus runs along the horizontal bottom edge of the foot end of the mattress over the full width thereof. This stitching 62 may be part of a continuous seam including the stitching 58 along the bottom edge of the longitudinal sides of the mattress.

To summarize the stitching pattern, the top sheet 50 is sewn to the bottom sheet only at the transverse stitch line 62 along the bottom edge of the foot of the bed at the intermediate area of the top sheet's end portion between the wrapped ends thereof, at the lower longitudinal stitch lines 58 along the bottom edges of the mattress sides at the bottom edges of the wrapped ends of the top sheet's end portion, and at the upper longitudinal stitch lines 60 along the top edges of the mattress sides at the folded connection of each wrapped end of the top sheet's end portion to the folded-under end of the respective lateral portion.

This particular folding and stitching of the originally rectangular top sheet 50 provides multiple benefits.

Firstly, the top sheet and bottom sheet are unattached with one another at the top edge of the foot of the bed, where the top sheet transitions from its main portion to its end portion and the bottom sheet transitions from its center portion to its foot end portion. The two sheets are also left unattached along the vertical corner edges of the mattress at the foot end of the bed, where the end portion 56 of the top sheet 50 wraps around these corners and the bottom sheet transitions from its foot end portion to its side portions. The upper layer of each lateral portion of the top sheet (i.e. everything other than the folded-under end 54 a thereof) is also not attached to the bottom sheet, and thus is movable relative to the bottom sheet with the main portion of the top sheet, from which the lateral portion's upper layer is a continuous integral extension.

Accordingly, the two sheets are not seamed together at the mattress edge between the top surface and foot of the mattress, thus leaving room for the central portion of top sheet to lift upward from the bottom sheet, as accommodated by the likewise movable upper layer of the lateral portion of the top sheet, in order to create a foot-accommodating space for occupants of the bed. On the other hand, the attachment of the sheets over a short distance from the foot of the bed along the longitudinal side edges of the mattress prevents the top sheet from being kicked off the mattress by foot movement, while the folding-under of the lateral portions of the top sheet at their ends and sewing of this folded-under end portion to the bottom sheet maintains a clean corner appearance by avoiding loose-hanging excess material spanning around the corners at the foot of the mattress.

Another way in which the combined top and bottom sheets 30 differ from the prior art is in the addition of pieces of loop material 40 to the side and head portions of the bottom sheet 32 and to the end portion 56 of the top sheet on the surfaces of these sheets that face outwardly away from the mattress for use in a hook and loop fastener arrangement, and in the addition of movable flaps 42 that are also attached to the outer surfaces of these same portions of the sheets to selectively cover and reveal and loop material pieces 40.

Each piece of loop material 40 is provided as an elongated strip running up the top or bottom sheet when the sheets are in place on the mattress. Each strip is positioned at a location around the mattress perimeter where a respective strap-end of the harness 10 reaches out from under the mattress. That is, each piece of loop material runs toward the rectangular boundary of the center or main portion of the sheet from at or near the free edge of the sheet at the perimeter thereof. In embodiments where the different portions of each sheet are integral parts of a unitary span of fabric, it will be appreciated that the ‘rectangular boundary’ of the center or main portion is an imaginary boundary that becomes realized at the perimeter of the top surface of the mattress when the sheets are in place on the mattress. In the illustrated embodiment, with six strap-ends extending out from under the mattress, there are six strips of loop material 40, one running up each of the four corners of the mattress, and one strip at a central location along each side portion of the bottom sheet so as to run centrally up the respective longitudinal sides of the mattress.

Each flap 42 is illustrated as a strip of fabric or other material that is sewn to the top or bottom sheet just above the top end of a respective one of the loop material strips 40, i.e. just past the end of the loop material strip 40 nearest the center or main portion 34 of the sheet. Each flap 42 can be pivoted about its sewn connection to the top or bottom sheet to move between a fastener-concealing position over the respective loop material strip 40, and a fastener-revealing position withdrawn from over the respective loop material strip 40 to allow access thereto. FIG. 2 shows the two flaps at the foot end of the bed in the fastener-concealing or closed positions, and the four remaining flaps in the fastener-revealing or open positions, while FIG. 3 shows all six flaps in the fastener-concealing positions.

Another piece of loop material is sewn to each flap 42 on the side or face thereof that faces toward the strip of loop material 40 on the sheets when the flap 42 is in the concealing position lying over the strip 40. With the same type of fastener material on the flap and the bottom sheet, the flap 42 does not fasten to the sheet when the flap is closed directly over the strip

However, as described above, each strap-end of the harness 10 has hook material attached to both sides of the strap. Accordingly, when the bottom sheet 32 is fitted on the mattress, each flap 42 is moved into the fastener-revealing position withdrawn from over the respective loop material strip 40, and the respective strap-end of the harness 10 poking out from under the mattress can be pulled upward and placed against the loop material strip 40 on the top or bottom sheet so that the hook material on the respective side of the strap will engage to the loop material strip 40, thus releasably fastening the strap-end to the combined sheets. During such fastening of the opposing strap-end to the bottom sheet, this strap-end is pulled sufficiently taught before engaging the hook and loop fastener so that the harness holds the bottom sheet taught between the opposing sides, ends or corners of the mattress to better secure the bottom sheet against movement, bunching or shifting on the top surface of the mattress. The straps thus provide improved retention of the bottom sheet versus use of the fitted-sheet's direct engagement to the mattress alone.

With each strap-end attached to the respective strip of loop material 40 on the sheets 32, 50, the respective flap 42 can be closed over the respective strap-end. In this fastener-concealing position over the strap-end and the loop material strip on the sheets thereunder, the loop material on the inside of the flap 42 engages the second piece of hook material on the strap-end, whereby the flap 42 covers up the strap-end and the hook and loop fastener that engages the strap-end to the sheets. The fastening of the flap to the strap-end and also adds further fastening strength to the connection between the strap and sheets. The flaps thus have dual functionality, both concealing the strap ends from sight, and further strengthening the connection between the bottom sheet and the securing straps of the harness.

While the illustrated embodiment employs diagonal corner straps and a central transverse strap, the number and orientation of straps may be modified into any of a number of different combinations, with the number and position of fastening sites on the sheets being likewise variable to suit the strap configuration. It will also be appreciated that the disclosed arrangement for attaching the securing straps of the harness to the bed sheets may be applied regardless of whether a combined top and bottom sheet arrangement is used. That is, a bottom sheet without an attached top sheet may be secured in place using the described strap configuration. In such instance, instead of being attached to the end portion of the top sheet, the two corner pieces of loop material and corresponding flaps at the foot end of the mattress would be attached to the foot end portion of the stand-alone bottom sheet, meaning that all the loop material pieces and covering flaps would be found on the side and end portions of the bottom sheet. Likewise, it will be appreciated that the advantageous features of the combined top and bottom sheet may be employed in embodiments lacking the sheet securing harness and corresponding harness attachment points on the combined sheets.

Although the detailed embodiment employs loop material on the sheets and flaps, and hook material on the straps of the harness, this configuration may be reversed without losing the functionality of the hook and loop fasteners. Alternatively, each strap could have opposite fastener materials on its two sides, with the sheets and flaps likewise having opposing fastener materials, but this is less preferred since it would require the harness be placed in a particular right-side-up orientation atop the box-spring to ensure proper function of the hook and loop fasteners. Other embodiments may employ fasteners of other types, but hook and loop fasteners are preferred.

Since various modifications can be made in my invention as herein above described, and many apparently widely different embodiments of same made within the spirit and scope of the claims without department from such spirit and scope, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense. 

1. A bed sheet for a mattress having a top surface, a bottom surface, a pair of first and second longitudinal sides, opposing head and foot ends, and corners defined between the longitudinal sides and the head and foot ends, the bed sheet comprising: a center fabric portion for overlying the top surface of the mattress; a plurality of hanging portions including: hanging head and foot portions for hanging over the head and foot ends of the mattress from opposing ends of the center fabric portion; first and second hanging side portions for hanging over the first and second longitudinal sides of the mattress from opposite sides of the center fabric portion; and sheet fastener elements disposed on multiple ones of said hanging portions; and flaps disposed on the multiples ones of said hanging portions and each being movable between a fastener-concealment position lying over at least one of the sheet fastener elements and a fastener-access position withdrawn from over said at least one of the sheet fastener elements.
 2. The sheet of claim 1 in combination with securing straps having strap fastener elements thereon that are positioned adjacent ends of said securing straps and selectively engagable to the sheet fastener elements of the bed sheet, the securing straps being dimensioned to span under the bottom surface of the mattress and reach upward therefrom at some or all of the sides, ends and corners of the mattress for attachment of the strap fastener elements to the sheet fastener elements to secure the bed sheet in place on the mattress, wherein movement of the flaps between the fastener-access and fastener-concealment positions enables exposure of the sheet fastener elements for attachment of the strap fastener elements thereto and subsequent concealment of said attachment from sight.
 3. The sheet of claim 1 wherein each flap has a flap fastener element thereon at a position that faces the sheet fastener element when said flap is in the fastener-concealment position over said sheet fastener element.
 4. The sheet of claim 3 wherein the flap fastener element and the sheet fastener element are non-engagable with one another.
 5. The sheet of claim 4 wherein the flap fastener element and the sheet fastener element are of a same one of either hook material or loop material of a hook and loop fastener.
 6. The sheet of claim 2 wherein a one of the flaps that is movable into and out of the fastener-concealment position over said sheet fastener element has a flap fastener element on a side of the flap that faces the sheet fastener element when said flap is in the fastener-concealment position, and a one of the securing straps for connecting to said sheet fastener element has a second strap fastener element on a side of said strap opposite the strap fastener element, the flap fastener element and the second strap fastener element being selectively engagable with one another.
 7. The sheet of claim 6 wherein the sheet fastener elements and flap fastener elements are of a same first type of fastener element, and the strap fastener elements on both sides of each strap are of a second type of fastener element engagable with the first type of fastener element.
 8. The sheet of claim 6 wherein the sheet fastener element and the strap fastener element are opposing ones of hook material and loop material to cooperatively form a first hook and loop fastener, and the flap fastener element and second strap fastener element are also opposing ones of the hook material and loop material to cooperatively form a second hook and loop fastener.
 9. The sheet of claim 8 wherein the sheet fastener element and the flap fastener element are the same one of either hook material or loop material.
 10. The sheet of claim 9 wherein the sheet fastener element and the flap fastener element are both loop material.
 11. The bed sheet claim 1 wherein the bed sheet is a combined top and bottom sheet in which the hanging foot portion is part of a top sheet of the combined top and bottom sheet and the hanging head and side portions are part of a bottom sheet of the combined top and bottom sheet, and the fastener elements include top sheet fastener elements on the top sheet and bottom sheet fastener elements on the bottom sheet.
 12. Securing straps for securing a bed sheet to a mattress by spanning of the straps beneath the mattress for connection of ends of said straps to the sheet at sheet fastener elements thereon at spaced apart positions around the perimeter of the mattress, the bed sheet having flaps movable into and out of fastener concealing positions over the sheet fastener elements and having flap fastener elements located on sides of the flaps that face the sheet fastener elements when the flaps are in the fastener concealing positions, wherein the securing straps comprise first and second strap fastener elements on opposite sides of each strap at a locations adjacent the ends of said straps, the first strap fastener element and the second strap fastener element being releasably engagable to the sheet fastener element and the flap fastener element, respectively.
 13. Combined top and bottom sheets for a mattress having a top surface, a bottom surface, a pair of first and second longitudinal sides, opposing head and foot ends, a top transverse edge defined between the top surface and the foot end, a bottom transverse edge defined between the bottom surface and the foot end, a top longitudinal edge defined between the top surface and each longitudinal side, a bottom longitudinal edge defined between the bottom surface and each longitudinal side, and upright corners defined between the foot end and the longitudinal sides, the combined top and bottom sheets comprising: a bottom sheet having a center portion for overlying the top surface of the mattress, head and foot portions for hanging over the head and foot ends of the mattress from opposing ends of the center portion, and first and second side portions for hanging over the first and second longitudinal sides of the mattress from opposite sides of the center portion; a top sheet comprising a main portion overlying the central portion of the bottom sheet, lateral portions overlying the side portions of the bottom sheet on opposite sides of the main portion of the top sheet, and an end portion overlying the foot portion of the bottom sheet at a respective end of the main portion of the top sheet, the end portion of the top sheet spanning beyond sides of the foot portion of the bottom sheet to also overlie an end of each side portion of the bottom sheet adjacent the foot portion thereof so that the end portion of the top sheet has wrapped ends that wrap around the corners of the mattress from the foot end of the mattress to the longitudinal sides thereof, and each lateral portion of the top sheet comprising a folded-under end that underlies a remainder of the lateral portion of the top sheet and that overlies and forms a folded connection with a respective one of the wrapped ends of the end portion of the top sheet; transverse stitching attaching the end portion of the top sheet to the foot portion of the bottom sheet in a transverse direction at a distance from the center portion of the bottom sheet so as to place the transverse stitching along the bottom transverse edge of the mattress; and upper longitudinal stitching attaching the top sheet to the bottom sheet in a longitudinal direction at the folded connection between the folded-under end of each lateral portion of the top sheet and the respective one of the wrapped ends of the end portion of the top sheet so as to place the upper longitudinal stitching along the top longitudinal edges of the mattress adjacent the foot end of the mattress, the remainder of each lateral portion of the top sheet being free of the longitudinal stitching so that only the folded-under end of said lateral portion is attached to the bottom sheet by said longitudinal stitching; wherein the bottom sheet and the top sheet are unattached to one another where the bottom sheet transitions from the central portion of the bottom sheet to the foot portion thereof so as allow relative movement between the sheets at the top transverse edge of the mattress.
 14. The combined top and bottom sheets of claim 13 wherein there is provided lower longitudinal stitching attaching the wrapped ends of the end portion of the top sheet to the side portions of bottom sheet in the longitudinal direction at a distance further from the center portion of the bottom sheet than the upper longitudinal stitching so as to place the lower longitudinal stitching along the bottom longitudinal edges of the mattress, the lower longitudinal stitching only partially spanning a length of the side portions of the bottom sheet in the longitudinal direction.
 15. The combined top and bottom sheets of claim 14 wherein the distances of the lower longitudinal stitching and the transverse stitching from the center portion of the bottom sheet are equal.
 16. The combined top and bottom sheets of claim 14 wherein the lower longitudinal stitching at each side portion of the bottom sheet forms a continuous seam with the transverse stitching.
 17. The combined top and bottom sheets of claim 13 wherein the transverse stitching fully spans the foot portion of the bottom sheet in the transverse direction. 